Battery pack

ABSTRACT

The present invention is applied to a power supply of a portable personal computer, for instance, to hold sheet-shaped secondary battery cells in a multi-layered arrangement with the same-side surfaces facing each other. In the above configuration, positive terminals and negative terminals of the secondary battery cells are connected to opposite surfaces of a terminal block to provide a series-parallel connection of these secondary batteries through the terminal block.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a battery pack, which is applicable toa power supply of a portable personal computer, for instance. Thepresent invention enables a more thickness reduction in the battery packof the personal computer etc. as compared with a conventional technologyto be attained by holding sheet-shaped secondary battery cells in amulti-layered arrangement with the same-side surfaces facing each other.

2. Background Art

Conventionally, a portable personal computer is adapted to be carriedfor being used in various places, and is thus fabricated in asmall-sized configuration and further in a small-thickness configurationso as to be convenient to carry.

Accordingly, the personal computer is also adapted to hold a drivingbattery pack in an exchangeable condition, so that an exchange of thebattery pack is effected as needed to prevent the personal computer frombeing placed into a difficult condition in use by running-down of abattery. In addition, the battery pack is also given in asmall-thickness configuration to prevent portability from beingdegraded.

Thus, the battery pack of this kind is configured by a series-parallelconnection of secondary battery cells specified as constituent units ofthe battery pack depending on a supply voltage and a power supplycapacity required for the personal computer. Further, in the batterypack, the secondary battery cells are given in the form of a sheet toprovide a multi-layered arrangement and further to provide a parallelarrangement so as to meet the series-parallel connection of thesesecondary battery cells.

By the way, in the battery pack of this kind, there has been a demandfor a more thickness reduction.

The battery pack, however, provides the series-parallel connection ofmore than one secondary battery cell at an inside as needed, so that acomplicated connection at the inside is required, and as a result, aremarkable degradation of productivity is predicted, in a case wheresize and thickness reductions of the battery pack are carried forward inthe present situation.

DISCLOSURE OF THE INVENTION

The present invention has been undertaken in view of the above pointsand is intended to propose a battery pack, which enables a morethickness reduction in the battery pack of a personal computer etc. ascompared with a conventional technology to be attained, morespecifically, the battery pack, which enables the thickness reduction tobe attained with a simple fabrication work.

To solve the above problems, according to the present invention, aconnection of a positive terminal and a negative terminal of eachsecondary battery cell located at the same side is provided through aterminal block to ensure that secondary battery cell pairs in amulti-layered arrangement with the same-side surfaces facing each otherare obtained.

In the secondary battery cells given in the form of a sheet, a biasarises in a thickness. Thereby, the secondary battery cells obtained inan overlap arrangement in the same direction cause the thickness bias tobe increased cumulatively, resulting in an increase of the wholethickness. On the contrary, the secondary battery cells obtained in themulti-layered arrangement with the same-side surfaces facing each otherenable a thickness reduction to be attained in such a manner that themulti-layered secondary battery cells may cancel the thickness bias eachother. Thereby, according to a configuration of the present invention,the secondary battery cell pairs obtained in the multi-layeredarrangement with the same-side surfaces facing each other canconstitutes a battery pack of a type having a smaller thickness than theconventional technology.

Also, according to the present invention, the terminal block in theabove configuration provides a connection of the positive terminals andthe negative terminals of the secondary battery cells to lands formed ata surface and a back surface, and also a series-parallel connection ofmore than one secondary battery cell through a wiring pattern betweenthe lands.

According to the configuration of the present invention, the connectionof more than one secondary battery cell to the terminal block may beobtained with a simple work by providing, through the terminal block,the connection of the positive terminal and the negative terminal ofeach secondary battery cell located at the same side. At this time, theterminal block provides the connection of the positive terminals and thenegative terminals of the secondary battery cells to the lands formed atthe surface and the back surface and also the series-parallel connectionof more than one secondary battery cell through the wiring patternbetween the lands, thereby enabling a connection work to be carried outsimply and surely, even if a complicated connection of more than onesecondary battery cell is required depending on various arrangements ofsecondary batteries, the number of secondary batteries and the number ofsecondary battery pairs to be connected in series, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a battery pack according to anembodiment of the present invention;

FIG. 2 is an exploded perspective view showing a secondary battery unitin the battery pack of FIG. 1; and

FIG. 3 is a plan view for use in a description of a terminal blockapplied to the secondary battery unit of FIG. 2.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will be described in detail inthe following with reference to the accompanying drawings appropriately.

(1) Configuration of the Embodiment

FIG. 1 is an exploded perspective view showing a battery pack accordingto an embodiment of the present invention. A battery pack 1 of FIG. 1 ismounted to a personal computer to supply power to the personal computerand also to be charged by the personal computer.

Specifically, the battery pack 1 is wholly in the form of a sheet, andis adapted to permit mounting to a back surface of the personal computerto be effected in a sliding manner. The battery pack 1 is formed so thata side specified as an inner side given by the mounting in the slidingmanner as described above may have a thickness larger than that of aside opposite to the inner side. The battery pack 1 is fabricated byarranging upper cases 4 and 5 in sequence on a secondary battery unit 3after the secondary battery unit 3 is housed in a lower case 2.

The lower case 2 used herein is formed by injection molding with a resinmaterial into an approximately rectangular configuration surrounded withwall surfaces. The lower case 2 has a notch 2A in a portion of amajor-side wall surface specified as a side that butts against thepersonal computer. The battery pack 1 is formed so that a connector 3Aof the secondary battery unit 3 is exposed to the outside through thenotch 2A, thereby providing an electrical connection with the personalcomputer through the connector 3A.

The secondary battery unit 3 is an assembly product obtained by aconnection of sheet-shaped secondary battery cells 6A to 6F applied tothe battery pack 1 through a terminal block which will be describedlater. The upper case 4 is formed by injection molding with a resinmaterial and holds the secondary battery unit 3 with the lower case 2covered in regard to a large thickness side of the secondary batteryunit 3. The upper case 5 is fabricated by applying pressing to a metalsheet material and holds the secondary battery unit 3 with the lowercase 2 covered in regard to a small thickness side of the secondarybattery unit 3. Thus, the battery pack 1 makes it possible to have asmaller thickness in its entirety by covering the lower case 2 in regardto the large thickness side with the resin-made upper case 4, and thelower case 2 in regard to the small thickness side with the upper case 5consisting of the metal sheet material as described above.

Thereby, in this embodiment, the lower case 2 and the upper cases 4 and5 are adapted, in regard to the secondary battery unit 3 obtained by theconnection of the sheet-shaped secondary battery cells 6A to 6F throughthe single terminal block, to form an external case that holds the abovesecondary battery unit 3 so as to permit the power of the abovesecondary battery unit 3 to be supplied to an external apparatus throughthe notch 2A.

FIG. 2 is an exploded perspective view showing the secondary batteryunit 3. The secondary battery unit 3 is fabricated by connecting aterminal block 7 and a temperature control component 9 in sequence to awiring substrate 8 after the connection of the secondary battery cells6A to 6F to the terminal block 7 is obtained, and then by bending thesecondary battery cells 6A to 6F about the terminal block 7 through aterminal portion as shown by arrows A and B. Specifically, infabrication as described above, the secondary battery unit 3 allows aninsulation tape 10 to be arranged between the terminal block 7 and thewiring substrate 8, and also an insulation tape 11 to be arrangedbetween the temperature control component 9 and the terminal block 7,thereby providing an assurance of the safety with these insulationtapes.

The secondary battery cells 6A to 6F used herein are non-aqueoussecondary battery cells of the same configuration, and are in the formof a rectangular sheet. The secondary battery cells 6A to 6F allowpositive terminals (which are terminals represented by a plus sign givento a root portion) and negative terminals (which are terminalsrepresented by a minus sign given to the root portion) to be located ata minor-side end surface. The secondary battery cells 6A to 6F areconfigured to have, at a corner of the minor-side surface, the negativeterminals, out of the positive terminals and the negative terminals ofthese secondary battery cells, and at the approximately center of theminor-side surface, the positive terminals. Thereby, the positiveterminals and the negative terminals in a one-sided arrangement areobtained so as to be one-sided in a longitudinal direction, with thesecondary battery cell side surfaces viewed from the front.

The secondary battery cells 6A to 6F are arranged three at a timeclosely side by side at the opposite longitudinal sides of the elongatedterminal block 7 so that the side surfaces configured with the positiveterminals and the negative terminals may face the terminal block 7. Thepositive terminals and the negative terminals are soldered to theterminal block 7. All the secondary battery cells 6A to 6F are locatedin the same direction such that the surfaces marked with the plus andminus signs may be observed from above when the arrangement of thesecondary battery cells 6A to 6F at the opposite sides of the terminalblock 7 is obtained as described above, thereby providing the one-sidedarrangement of the positive terminals and the negative terminals in areverse direction at the opposite sides of the terminal block 7.Thereby, when the secondary battery cells 6A to 6F are bent with anangle of about 90 degrees as shown by the arrows A and B, with thesecondary battery cells 6A to 6F located at the terminal block 7 asdescribed above, a close contact of the secondary battery cells 6A to 6Flocated at the opposite longitudinal sides of the terminal block 7 isobtained so that the same-side surfaces may face each other, therebyenabling a thickness reduction as the whole of the battery pack 1 to beattained.

Specifically, the secondary battery cells 6A to 6F of this kind arefabricated by rolling and pressing a multi-layered structure composed ofsheet-like members including a separator and an electrode etc., so thata bias arises inevitably in a thickness. The thickness bias is of coursesupposed to be a slight one that is not more than a crossing.Practically speaking, the secondary battery cells 6A to 6F obtained inthe multi-layered arrangement in the same direction, however, cause theabove slight thickness bias to be increased cumulatively, resulting inan increase of the whole thickness by a portion corresponding to theabove cumulative bias. On the contrary, the secondary battery cells heldin the multi-layered arrangement with the same-side surfaces facing eachother like this embodiment may cancel the above slight thickness biaseach other, thereby enabling a more reduction of the whole thickness tobe attained accordingly, as compared with a case where the secondarybattery cells in the overlapped arrangement in the same direction areobtained.

In the secondary battery cells 6A to 6F, the paired secondary batterycells 6A and 6D, those 6B and 6E and those 6C and 6F to be obtained inthe multi-layered arrangement in the same direction with the same-sidesurfaces facing each other are connected in parallel through theterminal block 7, thereby providing the secondary battery cell pairs 6Aand 6D, 6B and 6E and 6C and 6F obtained by a parallel connection. Inaddition, the secondary battery cell pairs 6A and 6D, 6B and 6E and 6Cand 6F obtained by the parallel connection are connected in series.

The terminal block 7 used herein is formed by covering the oppositesurfaces of a wiring pattern 12 consisting of a metal sheet materialwith an insulation sheet 13 consisting of a polyimide film, as shown inFIG. 3. The terminal block 7 is given in an elongated form, and has, inan approximately central portion extending in a longitudinal direction,elongated slits S at intervals to permit the terminal block 7 to bedouble-folded through the above central portion. The terminal block 7has, at the opposite sides of the slits S, the separate-shaped wiringpattern 12 consisting of the metal sheet material, and this wiringpattern 12 is formed to have partial broken portions at longitudinalprescribed intervals.

At the back surface side of the terminal block in FIG. 3, the insulationsheet 13 is formed to approximately cover the whole surface of thewiring pattern 12, while at the surface side thereof in FIG. 3, openingsadapted to form lands 14 used for a connection between the terminals ofthe secondary battery cells 6A to 6F and the wiring pattern 12 areformed at prescribed portions in the insulation sheet 13. Thereby, theterminal block 7 is configured to locate the wiring pattern 12 at thesurface side and the back surface side, like a so-called double-sidedwiring substrate, by double-folding the terminal block through portionsof the central slits S so that the side having the openings faces up,and also to have the lands 14 used for the connection between theterminals of the secondary battery cells 6A to 6F and the wiring pattern12.

Thereby, the terminal block 7 is adapted to provide the parallelconnection of the secondary battery cell pairs 6A and 6D, 6B and 6E and6C and 6F respectively obtained in the multi-layered arrangement withthe same-side surfaces facing each other. Thus, when the terminal block7 is used like the double-sided substrate as described above to providethe parallel connection of the secondary battery cell pairs 6A and 6D,6B and 6E and 6C and 6F, respectively, the above parallel connection maybe obtained by soldering the positive terminals and the negativeterminals of the secondary battery cells 6A to 6F to the lands 14, withthese terminals located at the back side and the surface side of theterminal block 7 in FIG. 2, thereby enabling the connection of thesecondary battery cells 6A to 6F to the terminal block 7 to be attainedwith a simple fabrication work and besides, without fail.

The terminal block 7 further has, in one of the separated wiringpatterns 12 obtained through the central slits S, projections 15projecting sideways from the insulation sheet 13, and also, in the otherwiring pattern 12, lands 16 located at portions corresponding to theprojections 15. The terminal block 7 is thus adapted to provide a seriesconnection of the secondary battery cell pairs 6A and 6D, 6B and 6D and6C and 6F obtained by the parallel connection by bending the terminalblock 7 through the portions of the slits S and by soldering theprojections 15 to the lands 16, with the projections 15 bent toward thelands 16. The above arrangements allow the terminal block 7 to provide aseries-parallel connection of the secondary battery cells 6A to 6F witha simple work, with the secondary battery cells 6A to 6F arranged backto back.

The terminal block 7 further has, at the side having the projections 15,projections 17 similar to the above projections 15, and also, at alongitudinal end, a projection 18. The projection 18 is located at thewiring pattern 12 to provide a connection to the positive terminals ofthe secondary battery cell pair 6C and 6F specified as the highestpotential-side cell pair obtained by the series-parallel connection ofthe secondary battery cells 6A to 6F as described above. The projections17 are located at the wiring pattern 12 at each connection point ofseries circuits of the secondary battery cells 6A to 6F. Theseprojections 17 and 18 are obtained to be projecting in an approximatelyright-angled bent shape toward the wiring substrate 8, respectively.

The wiring substrate 8 has slits permitting insertion of the projections17 and 18, and is adapted to provide a connection of the opposite endsof the secondary battery cell pairs 6A and 6D, 6B and 6E and 6C and 6Fobtained by the parallel connection by soldering the projections 17 and18 to the slits in an inserted condition. It is noted that in FIG. 3,the connection between the secondary battery cells 6A to 6F and thewiring substrate 8 through the terminal block 7 is represented withbattery symbols given by broken lines.

At the wiring substrate 8, the connector 3A and a charge/dischargecontrol circuit 20 adapted to control charge and discharge of thesesecondary battery cell pairs 6A and 6D, 6B and 6E and 6C and 6F arelocated. Specifically, the charge/discharge control circuit 20 iseffective in preventing overcharge and over-discharge of the secondarybattery cell pairs 6A and 6D, 6B and 6E and 6C and 6F by means ofmonitoring of inter-terminal voltages of the secondary battery cellpairs 6A and 6D, 6B and 6E and 6C and 6F, and further in controlling astop of the charge and the discharge by means of monitoring ofcharge/discharge currents. Further, prevention of abnormal discharge iseffected by monitoring temperatures of the secondary battery cells 6A to6F with a thermistor (not shown).

A temperature control component 9 is composed of a series circuit ofthermostats 9A and 9B and a thermal fuse 9C (See FIG. 2), and isarranged between the charge/discharge control circuit 20 and theconnector 3A, thereby providing prevention of accidents of the batterypack 1. Thus, the temperature control component 9 is configured so thatthe series circuit of the thermostats 9A and 9B and the thermal fuse 9Cis located in a clearance between the terminal block 7 and the positiveand negative terminals of the secondary battery cells 6A to 6F. Thereby,the battery pack 1 provides the arrangement of the temperature controlcomponent 9 by effectively utilizing a small inside space, and thisarrangement may be also applied to provide the battery pack of a smallersize and also with a smaller thickness.

(2) Operation of the Embodiment

In the battery pack 1 (see FIG. 3) having the above configuration, afterthe double-folded terminal block 7 is obtained, the projections 15 foruse in the series connection are bent toward the lands 16 and are thensoldered thereto into a completion of the fabrication of the terminalblock 7. In the battery pack 1, the above double-folding of the terminalblock 7 is adapted to obtain a wiring that provides the parallelconnection of the secondary battery cell pairs 6A and 6D, 6B and 6E and6C and 6F through the inter-land 14-wiring pattern 12 consisting of themetal sheet material and having, at the surface and the back surface,the lands that provides the connection of the positive terminals and thenegative terminals of the secondary battery cells 6A to 6F. Also, theconnection between the projections 15 and the lands 16 is adapted toobtain the connection of the wiring pattern 12 that provides the seriesconnection of the secondary battery cell pairs 6A and 6D, 6B and 6E and6C and 6F obtained by the parallel connection.

In the battery pack 1, the secondary battery cells 6A to 6F are arrangedthree at a time side by side at the opposite sides of the terminal block7 so that the positive terminals and the negative terminals may face theterminal block 7-side (See FIG. 1). Also, the positive terminals and thenegative terminals are connected to the lands 14 at the surface side andthe back surface side of the terminal block 7 by soldering,respectively. Thereby, the battery pack 1 may provide a two-by-twoparallel connection of the secondary battery cells 6A to 6F, and alsothe series connection of parallel circuits of these secondary batterycells.

In the battery pack 1, the connector 3A and the charge/discharge controlcircuit 20 are packaged on the wiring substrate 8 separately, and theprojections 17 and 18 of the terminal block 7 obtained by the connectionof the secondary battery cells 6A to 6F are soldered in an insertedcondition to the slits of the wiring substrate 8, thereby providing theconnection of the secondary battery cells 6A to 6F to thecharge/discharge control circuit 20. Likewise, the series circuit of thethermostats 9A and 9B and the thermal fuse 9C that are obtained byassembling with a separate process is connected to the wiring substrate8 through the terminal block 7-side, thereby providing acharge/discharge path between the charge/discharge control circuit 20and the connector 3A.

In the battery pack 1, when the connection of the secondary batterycells 6A to 6F and others to the wiring substrate 8 is obtained asdescribed above, the terminals of the secondary battery cells 6A to 6Fare bent, thereby providing the secondary battery unit 3 in which thesecondary battery cell pairs 6A and 6D, 6B and 6E and 6C and 6F obtainedby the parallel connection are held in the multi-layered arrangementwith the same-side surfaces facing each other (See FIG. 2), and thewiring substrate 8 and the terminal block 7 are located at the terminalside of the secondary battery cell pairs 6A and 6D, 6B and 6E and 6C and6F.

The battery pack 1 is fabricated by arranging the upper cases 4 and 5 insequence on the secondary battery unit 3 obtained as described above,after the above secondary battery unit 3 is housed in the lower case 2.

The battery pack 1 fabricated as described above may not cause thecumulative increase of the thickness bias in each of the secondarybattery cells 6A to 6F, in other words, may provide mutual cancellationof the thickness bias among the secondary battery cells 6A to 6Fobtained in the multi-layered arrangement by allowing the secondarybattery cell pairs 6A and 6D, 6B and 6E and 6C and 6F obtained by theparallel connection to be held in the multi-layered arrangement with thesame-side surfaces facing each other, thereby enabling a more reductionof the whole thickness as compared with the conventional technology tobe attained.

A complicated connection is however, required for the secondary batterycell pairs 6A and 6D, 6B and 6E and 6C and 6F obtained in themulti-layered arrangement with the same-side surfaces facing each other,when the parallel connection is provided in pairs of two secondarybattery cells 6A and 6D, 6B and 6E and 6C and 6F, as compared with acase where the multi-layered arrangement in the same direction is given.Specifically, when the positive terminals and the negative terminals arearranged in a symmetrical position about a centerline of each secondarybattery cell, it may also be possible that short-circuiting accidentsoccur between the positive terminals and the negative terminals in thesecondary battery cells obtained in the multi-layered arrangement.

On the contrary, the present battery pack 1 may provide prevention ofthe occurrence of the above short-circuiting accidents by allowing thepositive terminals and the negative terminals of the secondary batterycells 6A to 6F to be arranged one-sided in a longitudinal direction atthe side surface configured with these positive and negative terminals.In addition, a simple work requiring only soldering of the positiveterminals and the negative terminals to the corresponding lands 14 afterdistribution of these terminals to the surface and the back surface ofthe terminal block 7 may be applied to provide the connection of thesecondary battery cells 6A to 6F surely, with a wrong connection avoidedeffectively, by forming, at the surface and the back surface of theterminal block 7, the wiring pattern 12 for use in the connection of thepositive terminals and the negative terminals, with these terminalsarranged one-sided as described above.

In addition, a power loss attributable to the above wiring pattern maybe minimized by providing the terminal block 7 fabricated by coveringthe opposite surfaces of the wiring pattern 12 consisting of the metalsheet material with the insulation sheet 13.

In addition, the arrangement of the charge/discharge control circuit 20adapted to control the charge and the discharge of the secondary batterycell pairs 6A and 6D, 6B and 6E and 6C and 6F may be obtained with theeffective use of a space within the battery pack 1 by providing theconnection of the wiring substrate 8 to the terminal block 7 in themulti-layered arrangement. This arrangement may be also applied toprovide the thickness and size reductions of the whole configuration.

(3) Effects of the Embodiment

The above configuration enables a more thickness reduction in thebattery pack of the personal computer etc. as compared with theconventional technology to be attained by holding the sheet-shapedsecondary battery cells in the multi-layered arrangement with thesame-side surfaces facing each other.

Also, the short-circuiting accidents and the like in between thesecondary battery cells obtained in the multi-layered arrangement may beeffectively prevented in the secondary battery by providing the positiveterminals and the negative terminals that are arranged one-sided in thelongitudinal direction.

Also, the power loss reduction may be attained by providing the terminalblock fabricated by covering the opposite surfaces of the wiring patternconsisting of the metal sheet material with the insulation sheet.

Also, the thickness and size reductions of the whole configuration maybe attained by connecting the wiring substrate mounted with thecharge/discharge control circuit adapted to control the charge and thedischarge of the secondary battery cells to the terminal block in themulti-layered arrangement so as to supply the power of the secondarybattery cells to the external apparatus through the wiring substrate.

Also, the simple fabrication work may be applied to attain the thicknessreduction in the above configurations by connecting the positiveterminals and the negative terminals of the secondary battery cells tothe opposite surfaces of the terminal block to provide theseries-parallel connection of the secondary batteries through theterminal block.

Specifically, the above configuration of the terminal block may provideprevention of the short-circuiting accidents and the like in between thesecondary battery cells obtained in the multi-layered arrangement,besides, facilitation of the connection to the terminal block and alsosure prevention of the wrong connection by providing, in the secondarybattery, the positive terminals and negative terminals that are arrangedone-sided in the longitudinal direction.

Also, the terminal block having, at the surface and the back surface,the lands for use in the connection may be fabricated, with the powerloss reduction attained, in the above configuration of the terminalblock by providing the terminal block fabricated into an approximatelydouble-folded shape by covering the opposite surfaces of the wiringpattern consisting of the metal sheet material with the insulationsheet.

Also, the thickness and size reductions of the whole configuration maybe attained in the above configuration of the terminal block by allowingthe wiring substrate mounted with the charge/discharge control circuitadapted to control the charge and the discharge of the secondary batterycells to be connected in the multi-layered arrangement so as to supplythe power of the secondary battery cells to the external apparatusthrough the wiring substrate.

(4) Other Embodiments

Although the above embodiment has been described on a case where theterminal block is used in the double-folded shape obtained through thelongitudinally extending slits, the present invention is not limited tothe above embodiment, and it is allowable to set a bending directionvariously as needed.

Although the above embodiment has been described on a case where twopieces of secondary battery cells are connected in parallel to providethe series connection composed of three parallel connections, thepresent invention is not limited to the above embodiment, and it isallowable to apply the present invention widely to a case where variousnumbers of secondary battery cells are adapted to provide the parallelconnection and further to a case where various numbers of secondarybattery cell layers are adapted to provide the series connection.

Although the above embodiment has been described on a case where thepresent invention is applied to the battery pack of the personalcomputer, the present invention is not limited to the above embodiment,and it is allowable to apply the present invention widely to the batterypacks of various kinds of apparatuses.

As described above, according to the present invention, the morethickness reduction in the battery pack of the personal computer etc. ascompared with the conventional technology may be attained by holding thesheet-shaped secondary battery cells in the multi-layered arrangementwith the same-side surfaces facing each other.

The simple fabrication work may be applied to attain the thicknessreduction in the above configuration by connecting the positiveterminals and the negative terminals of the secondary battery cells tothe opposite surfaces of the terminal block to provide theseries-parallel connection of the secondary battery cells through theterminal block.

INDUSTRIAL APPLICABILITY

The present invention relates to the battery pack, which is applicableto the power supply of the portable personal computer, for instance.

1. A battery pack, characterized by having: a secondary battery unitobtained by a connection of more than one sheet-shaped secondary batterythrough a terminal block; and an exterior case adapted to hold saidsecondary battery unit so as to allow a power of said secondary batteryunit to be supplied to an external apparatus; characterized in that saidsecondary battery has, on one end surface, a positive terminal and anegative terminal sequentially arranged side by side in a longitudinaldirection; said secondary battery unit has more than one secondarybattery cell pair obtained by a multi-layered arrangement of said morethan one secondary battery cell with said positive and negativeterminals located at the same side, provides a sequentially side-by-sidearrangement of said more than one secondary battery cell pair with saidpositive and negative terminals located at the same side, and isfabricated by providing, through said terminal block, a connection ofsaid positive terminal and said negative terminal of each secondarybattery cell located at the same side; and each of said secondarybattery cell pairs is provided in a multi-layered arrangement with thesame-side surfaces facing each other.
 2. The battery pack according toclaim 1, wherein said secondary battery has the positive terminal andthe negative terminal arranged one-sided in said longitudinal direction.3. The battery pack according to claim 1, wherein said terminal block isfabricated by covering the opposite surfaces of a wiring patternconsisting of a metal sheet material with an insulation sheet.
 4. Thebattery pack according to claim 1, wherein said terminal block allows awiring substrate mounted with a charge/discharge control circuit adaptedto control charge and discharge of said secondary battery cells to beconnected thereto in a multi-layered arrangement so as to supply thepower of said secondary battery cells to said external apparatus throughsaid wiring substrate.
 5. The battery pack according to claim 1, whereinsaid terminal block provides a connection of the positive terminals andthe negative terminals of said secondary battery cells to lands formedat a surface and a back surface, and also a series-parallel connectionof said more than one secondary battery cell through a wiring patternbetween said lands.
 6. The battery pack according to claim 5, whereinsaid secondary battery has the positive terminal and the negativeterminal arranged one-sided in said longitudinal direction.
 7. Thebattery pack according to claim 5, wherein said terminal block isfabricated in an approximately double-folded shape by covering theopposite surfaces of the wiring pattern consisting of a metal sheetmaterial with an insulation sheet.
 8. The battery pack according toclaim 5, wherein said terminal block allows a wiring substrate mountedwith a charge/discharge control circuit adapted to control charge anddischarge of said secondary battery cells to be connected thereto in amulti-layered arrangement so as to supply the power of said secondarybattery cells to the external apparatus through said wiring substrate.